@keyframes move {
    from {margin-left: 1em;}
    50% {margin-left: 8em;}
    to {margin-left: 1em;}
}

body, html {
    box-sizing: border-box;
    height: 100%;
    width: 100%;
    font-family: sans-serif;
    font-size: 14px;
}

#background {
    display: flex;
    height: 100%;
    width: 100%;
    background-image: url(../img/back.jpg);
    background-size: 100% 100%;
    background-repeat: no-repeat;
    opacity: 0.9;
}

#guide {
    display: flex;
    flex-direction: row;
    flex-wrap: nowrap;
    position: absolute;
    width: 100%;
    height: 5%;
    margin: 1em !important;
    /* background: rgb(0, 38, 85); */
}

#guide>li {
    display: inline-block;
    list-style-type: none;
}

#right {
    animation: move 5s infinite;
    flex-grow: 15;
    font-size: 1.5em;
    color: white;
    margin: 0.2em;
    padding: em;
}

#right::after {
    border: 1px solid whitesmoke;
}

#left {
    width: 5%;
    flex-grow: 1;
    margin: 0.2em;
    margin-right: 2em;
    text-align: center;
    font-size: 1.2em;
    color: whitesmoke;
    padding: 0.15em;
    border: 1.5px solid white;
    overflow: hidden;
}

#left:hover {
    cursor: pointer;
    transition: 500ms;
    border-radius: 1em;
    color: rgb(255, 255, 255);
}

#font {
    margin: auto;
    font-size: 3em;
    color: rgb(255, 242, 221);
}

#build {
    display: block;
    padding-bottom: 0.5em;
    margin-bottom: 1em;
    border-bottom: 2px solid white;
}

#grop {
    display: block;
    font-size: 0.5em;
}

#button {
    display: inline-block;
    width: 15%;
    height: 1.5em;
    margin-top: 4em;
    margin-left: 10em;
    text-align: center;
    font-size: 0.4em;
    border: 1px solid white;
}

#button:hover{
    background: rgba(184, 177, 177,0.5);
    color: white;
    cursor: pointer;
    transition: 500ms;
    border-radius: 1em;
}

#introduce {
    display: flex;
    width: 100%;
}

#container {
    margin: auto;
    width: 80%;
    height: 60%;
    
}

